My suggestion is to get your laptop cleaned detailed from inside. When laptop is used for 6 months or more, the cooling sistem is full of dirt. You can try to do it by yourself, but i dont suggest you to do that. Proper skills are required.
Also, changing termal paste will reduce heating also.
If this is too expensive for you, maybe you can get yourself "laptop cooling platform". They are usualy very cheap but they do great job. Try to google for them.